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Carl Eyman
05-19-2003, 5:52 PM
Not sure where to post this question, but I'm told all the thinking people are here; so here goes: I am making a batch of Chippendale style dining chairs. The front legs are typical Chip. style, ball & claw feet, cabriole, decorated knee, knee block returns. As I was assembling chair # 4 today I chose a pair of legs from the supply, and oh the horror of it all! These legs were carved about 3 months ago. each of this pair have cracks that have developed. One starts at the foot and travels all the way up the leg through the calf. It stops there. It is wide enough to just barely stick a paper into and maybe 1/4" deep. The other leg has a crack that starts at the bottom of the ball goes up through the ball into the instep of the foot and stops there. It is a little less than the thickness of a piece of paper. Since I can't probe it, I don't know the depth. From what I see on the bottom of the foot and on the surface of the instep it may be 1/2" deep.

Question: What to do? Throw 'em out and make new ones? Flow super glue into crack and sand to fill crack? (If it splits no further, this might fill up the crack under the varnish so it wouldn't show. How about drilling one or two 1/4" holes horizontally and peg them with mahogany dowels. Would this pevent further splitting.?

Oh! woe is me.

Tom Scott
05-19-2003, 6:06 PM
What a bummer.
I'm no expert in this field, so hopefully someone else will chime in. Of the 2 options you listed, I would go the super-glue-and-sand route. With a little luck, the wood has split as much as it's going to, in which case this should work fine. Another option would be to use a tinted epoxy. I haven't tried this myself, but this seems like a case where it would be appropriate.
Like I said, maybe someone with a little more experiece will offer up their opinion.

Tom

Carl Eyman
05-19-2003, 6:50 PM
At this point I don't believe the crack is wide enough to accept the epoxy. Since the finish will be a fairly dark "cuban red" I'm not worried much about their showing so long as they don't split more and break th surface of the varnish. That is why I mentioned the dowels - to stop further splitting.

Jim Becker
05-19-2003, 6:51 PM
Carl, it sounds like those legs were built from lumber that was not at a low enough moisture content. (MC) The most plausible explanation is that after you milled them out and carved, etc, they dried further, and since they dried faster on the outside surfaces, cracking occurred. You can certainly try the super glue fix, but there is no guarantee that the cracking will not continue or reappear in the legs.

If you do not already have one, a moisture meter is a pretty essential tool to have in your shop, not only to check rough lumber when you are buying it, but to check the stock you've chosen for a project to insure that all components will be at equal MC. This is regardless of whether you will be working with hand tools or with power-hungry monster machines...

Paul Barnard
05-19-2003, 7:53 PM
Carl,
It is unlikely glue will completely fix your problem. If the wood wants to split it will, it will just move over a smidge if it can't continue where you have glued. If you are intent on recovering the legs then you will need some cross grain strength in the from of a dowel as you suggest

Carl Eyman
05-19-2003, 8:18 PM
Keep in mind I have 10 chairs to make. I have parts for 5 of them ready for assembly. Here is what I think I'll do:

I'll repair these legs and have them finished (stained, varnished,etc.) with the first five chairs. But I'll make a new set of legs as a part of the next batch of 5. I'll use them here for chair 4 and if the repaired pair are still in good condition when I am assembling the second set of five, make a decision on whether or not to use them.

If Jim Becker is still aboard, what moisture content should I be looking for?

I don't want to make the same mistake twice. Thanks all.

Jim Becker
05-19-2003, 8:26 PM
Originally posted by Carl Eyman
If Jim Becker is still aboard, what moisture content should I be looking for?

You didn't say how your sourced your material so here are some general thoughts.

Ideally, wood for furniture would be in the 8 % MC range for KD, but air dried lumber is usually fine if it is 12% MC or lower. But remember, you're using thicker material if you're milling your legs out of solid stock without glue-ups...they can take three to four times as long to dry as 4/4 or 5/4 flat boards if air drying.

Now, if you bought the stock for your legs from a commercial supplier and they were sold as being "dry", you have a bone to pick with them. That's another area that a moisture meter can come into play!

Dave Anderson NH
05-20-2003, 11:08 AM
I built Sue's breakfast table last year. I cracked one of the legs (not a moisture problem, just me) and used a good coat of super glue and then sanded. It worked out just fine and I can't even tell which leg was the one I repaired. I think the doweling would be a mistake unless you use ones shorter than the hole you drill and then cap the hole with a plug cut from long grain and oriented very carefully. End grain showing would really stick out.

Fortunately, with the coarse grain of mahogany repairs are fairly easy to hide. If you decide to buy more stock, rough cut the leg blanks on the bandsaw and let them sit 2-4 weeks before starting the carving and the detail work. It could save you a lot of disappointment and wasted effort if something cracks again.

Good luck, I'm sure you will come thru this just fine.

Doug Littlejohn
05-20-2003, 5:32 PM
Hi there DCarl,

1. While far from being an expert (or even a novice) I would go the superglue route (thin stuff so it wicks in). Then clamp tightly to hopefully close the gap.

2. Your idea of making another set to cover if it doesn;t work sounds good.

3. While there are standard "rules" for MC, I believe it is even more important that it be at the same as other 'acclimated' wood is in your location. Depending on the time of year, your local MC (as a result of your humidity) could well be several percent more or less. That being said, any wood you work with MUST be acclimated to the local environment. Of course if you are building it to send to a very different climate, that changes things (as well as complicates) a bunch!

4. I would NOT use a dowel on a piece that is being built (only maybe on one I'd had for years and years).

I hope this may help in some way.